Laoshan District Adjustable Office Chair Repair

For the repair of adjustable office chairs in Laoshan District, you can refer to the following steps for troubleshooting and handling:

1. Check the Adjustment Lever
The adjustment lever connects the pneumatic spring to the chair seat and controls height adjustment. If it is loose or damaged, the lifting function will fail. First, check if the screws on the adjustment lever are loose and tighten them with tools. If the lever itself is damaged (e.g., broken or deformed), it needs to be replaced with a new one.

2. Check the Pneumatic Spring (Pneumatic Rod)
Pneumatic rod failure is the main cause of lifting problems, accounting for over 70%. Common manifestations include:

• Complete inability to lift or lower: The internal valve is stuck or the seal has failed.
• Slow sinking: Seal aging leads to high-pressure nitrogen leakage (accompanied by a 'hissing' sound when leakage exceeds 10%).
• Lifting stuttering or abnormal noise: Internal structure wear or lubrication failure.
  Solution: The pneumatic rod is a one-time sealed component and needs to be replaced as a whole. Strictly follow safety regulations during operation:
• Removing the old rod: Invert the chair and use a pipe wrench to rotate the metal collar connecting the hydraulic rod to the five-star base counterclockwise (reverse thread). If necessary, drip lubricating oil to assist. Remove the old rod according to the connection method (snap-ring type or screw-fixed type).
• Measuring and purchasing a new rod: Measure the total length (shortest length when fully compressed), tube diameter (common Class 3 has an inner tube of 33mm/outer tube of 48mm, Class 4 is thicker), and stroke (difference between maximum extension and minimum compression). Bring the old rod or a size photo and choose a new rod with SGS/BIFMA certification, priced at approximately 30-100 yuan.
• Installing the new rod: Clean the interfaces of the five-star base and the chair seat chassis, tighten the bottom thread of the new rod clockwise, insert it into the chair seat chassis, and secure it with a snap ring or screw. Test if the lifting is smooth.

3. Check the Base Casters
Excessive resistance from the casters may cause lifting difficulties. Invert the chair, remove the casters, clean dust and debris, add lubricating oil to the axles, and reinstall them.

4. Check the Lifting Rod Screws
If the screws at the connection between the lifting rod and the base are loose, shaking the chair will produce a 'clunking' sound. Tighten the screws with an Allen wrench (commonly 4mm/5mm), apply thread locker (such as Loctite 243) to prevent secondary loosening, with a tightening torque of 3-4N·m for aluminum alloy and 5-6N·m for steel.

5. Check the Chair's Balance
An uneven floor or a height difference of over 1cm between the four legs can cause a shift in the center of gravity and accelerate seal wear on the pneumatic rod. This can be improved by adding counterweights (recommended weight = user's weight × 0.1kg) or adjusting the height difference between the feet to ≤3mm.

6. Check the Chair Cushion
Poor-quality sponge cushions that sag can directly compress the pneumatic rod. If the rebound time after pressing exceeds 3 seconds or the thickness decreases by 30%, the cushion needs to be replaced (especially for users weighing over 80kg).

7. Check the Electric Circuit (for electric adjustable chairs only)
Cold solder joints on the circuit board, poor switch contact, or damaged power cords can cause lifting malfunctions. After disconnecting the power and discharging, use a multimeter to test the motor voltage (standard 24V ± 10%), check the oxidation of the switch contacts, and replace the microswitch if necessary. Wear insulating gloves during operation.

If the above methods are ineffective, it is recommended to contact professional repair personnel to avoid safety issues caused by improper operation.